Showcase

ABSTRACT

An object is to provide a showcase in which appropriate illumination is realized by an LED illumination apparatus having a high durability against turning ON/OFF and capable of securing a predetermined illumination intensity even under an environment at a low temperature and in which dew condensation caused in a door frame can effectively be suppressed. The showcase in which the inside of a display chamber constituted in a main body so as to display commodities is illuminated by the LED illumination apparatus includes a glass door which openably closes an opening of the display chamber, and a metal door frame which is provided in the main body so as to constitute an opening edge of the display chamber and on which the glass door abuts, and the LED illumination apparatus is provided on the surface of the door frame on the side of the display chamber in a heat exchange relation.

BACKGROUND OF THE INVENTION

The present invention relates to a showcase in which the inside of adisplay chamber for displaying commodities is illuminated by an LEDillumination apparatus.

Heretofore, in a supermarket or a convenience store, a showcase has beenused in which a display chamber is constituted in a main bodyconstituted of an insulating box body having an open front surface andin which the front-surface opening is openably closed by a rotary glassdoor. To appropriately maintain the closed state of the door for use insuch a showcase, a door frame made of a metal is attached to an openingedge of a main body on which the door abuts, and a magnet-embeddedpacking is attached to the outer edge of the door on an opening side.

In the closed state, the door rotatable around one side of the openingcomes in close contact with a metal frame member on the opening side bythe magnetic force of a magnet provided in the door, and the closedstate is maintained in a state in which cold air is effectivelyprevented from leaking.

The above-mentioned door frame comes in contact with the outside, andcomes close to the inside of the display chamber cooled to apredetermined temperature, so that dew condensation easily occurs owingto a difference between an outside temperature and a temperature in thedisplay chamber. There occurs a disadvantage that dew adheres to such anopening to wet the inside of the display chamber, the installation floorsurface of the showcase or the like or a disadvantage that the dew fliesand scatters by the opening/closing operation of the door.

Consequently, heretofore, to avoid the generation of such dewcondensation in advance, in the opening edge of the main body on whichthe door abuts, a heater has been embedded in the inner surface of thedoor frame made of the metal, and the surface of the door frame on theside of the glass door has been heated constantly by the energization ofthe heater.

On the other hand, to illuminate commodities displayed in the displaychamber, a fluorescent lamp or an LED illumination apparatus has beenused as an illumination apparatus (e.g., see Japanese Patent ApplicationLaid-Open No. 5-34047).

Moreover, the fluorescent lamp or the LED illumination apparatus for useas the illumination apparatus generates heat itself by the energization.In the showcase in which the inside of the display chamber is cooled bya cooling apparatus for use, since the illumination apparatus isprovided in the display chamber, there is a problem that the coolingefficiency of the cooling apparatus is lowered by the illuminationapparatus generating the heat when lit.

To solve the problem, it is considered that the turning ON/OFF or theillumination intensity of the illumination apparatus be adjusted,depending on whether or not a customer is present. However, since thedisplay chamber as a cooling space has a low temperature, the heretoforeused fluorescent lamp requires a certain degree of time for realizing apredetermined illumination intensity immediately after the lamp isturned on. Moreover, the fluorescent lamp is frequently turned on/off,which causes a problem that the life of the fluorescent lamp itselfshortens.

On the other hand, the heater for use in heating the door frame isconstantly energized regardless of the turning ON/OFF of theillumination apparatus provided in the display chamber. Since the heatgenerated by the heater leaks into the display chamber, there is also aproblem that the cooling efficiency of the cooling apparatus lowers.

SUMMARY OF THE INVENTION

The present invention has been developed to solve a conventionaltechnical problem, and an object thereof is to provide a showcase inwhich appropriate illumination can be realized by an LED illuminationapparatus having a high durability against turning ON/OFF and capable ofsecuring a predetermined illumination intensity even under anenvironment at a low temperature and in which dew condensation caused ina door frame can effectively be suppressed.

According to the invention of a first aspect, there is provided ashowcase in which the inside of a display chamber constituted in a mainbody so as to display commodities is illuminated by an LED illuminationapparatus, characterized by comprising: a glass door which openablycloses an opening of the display chamber; and a metal door frame whichis provided in the main body so as to constitute an opening edge of thedisplay chamber and on which the glass door abuts, wherein the LEDillumination apparatus is provided on the surface of the door frame onthe side of the display chamber in a heat exchange relation.

A showcase of the invention of a second aspect is characterized in thatthe above invention further comprises: an electric heater which heatsthe surface of the door frame on the side of the glass door, wherein theelectric heater is energized at a time when the LED illuminationapparatus is turned off.

A showcase of the invention of a third aspect is characterized in thatin the invention of the first aspect, the LED illumination apparatusincludes an electric heater, and the electric heater is energized at atime when the LED illumination apparatus is turned off.

According to the invention of the first aspect, the showcase in whichthe inside of the display chamber constituted in the main body so as todisplay the commodities is illuminated by the LED illumination apparatuscomprises the glass door which openably closes the opening of thedisplay chamber; and the metal door frame which is provided in the mainbody so as to constitute the opening edge of the display chamber and onwhich the glass door abuts. The LED illumination apparatus is providedon the surface of the door frame on the side of the display chamber inthe heat exchange relation. In consequence, the heat of the LEDillumination apparatus itself generated by energization can betransmitted to the surface of the door frame on the side of the displaychamber, and the dew condensation of the door frame which easily causesthe dew condensation owing to a difference between an outside airtemperature and a temperature in the display chamber can effectively besuppressed.

Consequently, it is possible to effectively avoid a disadvantage thatthe dew condensation occurs in the door frame to wet the inside of thedisplay chamber, the installation floor surface of the showcase or thelike. Moreover, it is possible to avoid a disadvantage that dew fliesand scatters owing to the opening/closing operation of the glass door.

According to the invention of the second aspect, in addition to theabove invention, the showcase further comprises the electric heaterwhich heats the surface of the door frame on the side of the glass door,and the electric heater is energized at a time when the LED illuminationapparatus is turned off. Even in a case where the LED illuminationapparatus is turned off and the door frame cannot be heated by the heatgenerated by the apparatus itself, when the LED illumination apparatusis turned off, the electric heater for heating the surface of the doorframe on the glass door side can be energized to effectively suppressthe dew condensation of the door frame.

Moreover, according to the invention of the third aspect, in addition tothe invention of the first aspect, the LED illumination apparatusincludes the electric heater, and the electric heater is energized at atime when the LED illumination apparatus is turned off. In consequence,even in a case where the LED illumination apparatus is turned off andthe door frame cannot be heated by the heat generated by the apparatusitself, when the LED illumination apparatus is turned off and theelectric heater is energized, the heat generated by the electric heatercan be transmitted to the surface of the door frame on the displaychamber side to effectively suppress the dew condensation of the doorframe.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a showcase to which the present invention isapplied;

FIG. 2 is a partially enlarged sectional view of the showcase of FIG. 1;

FIG. 3 is a side view of an illumination apparatus;

FIG. 4 is a partially enlarged view of FIG. 3;

FIG. 5 is a partially enlarged view of a substrate;

FIG. 6 is an electric block diagram of a control apparatus;

FIG. 7 is an electric circuit diagram showing the connection of a persondetecting sensor; and

FIG. 8 is a partially enlarged sectional view of a showcase as anotherembodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An embodiment of the present invention will hereinafter be describedwith reference to the drawings. FIG. 1 shows a front view of a showcase1 to which the present invention is applied, and FIG. 2 shows apartially enlarged sectional view of the showcase 1. The showcase 1 is alow-temperature showcase installed in a supermarket, a convenience storeor the like, and a main body is constituted of an insulating box body(an insulating wall) 2 having an open front surface.

This insulating box body 2 is constituted of an outer box 3 having anopen front surface and formed of a steel plate; an inner box (not shown)assembled in this outer box 3 with a space being left between the innerbox and the outer box, having an open front surface, and formed of asteel plate or a hard resin; and an insulating material with which aspace between the outer box 3 and the inner box is foam-filled and whichis made of foam polyurethane.

A display chamber 5 is constituted in this inner box, and afront-surface opening 6 of the display chamber 5 across the upper andlower ends of the opening is openably closed by a plurality of (three inthe present embodiment) rotary glass doors 7, 7 and 7 through which theinside can be seen. Each of the glass doors 7 is constituted of a framemember 7A constituting a door edge, and a glass plate 7B which isprovided in the frame member 7A and through which the inside can beseen, and the rear surface of the frame member 7A is provided with agasket 7C.

In the edge of the front-surface opening 6 of the insulating box body 2,a plurality of (in this case, the three doors 7 are provided, and hencetwo) pillars 8 are vertically provided with a predetermined space beingleft between the pillars. This pillar 8 is constituted of a verticallyextending pole-like insulating material 40, a door frame 45 which abutson the front surface of the insulating material 40 to constitute thefront surface of the pillar 8, and an illumination attachment portion 46provided so as to perform heat exchange between the portion and the doorframe 45.

The insulating material 40 is provided with a hollow portion 40Apositioned substantially in the center of a transverse section so as tovertically extend. The door frame 45 abuts on the back surface (thegasket 7C) of the glass door 7 which openably closes the front-surfaceopening 6 of the insulating box body 2, and is constituted of asatisfactorily thermally conductive metal material. Moreover, theillumination attachment portion 46 is constituted of a satisfactorilythermally conductive metal material in the same manner as in the doorframe 45. The front end of the portion is provided so as to abut on therear surface of the door frame 45, and the end of the portion is bentrearwards along the hollow portion 40A of the insulating material 40,and formed so as to extend rearwards as much as a predetermineddimension from the rear wall of the insulating material 40. The rear endof this illumination attachment portion 46 is formed so as to tilt asmuch as a predetermined angle behind the center of the pillar 8.

It is to be noted that as described later, the illumination attachmentportion 46 may be constituted of a plurality of (in this case, two)plate-like members which abut on the inner walls (side surfaces) of thehollow portion 40A of the insulating material 40 so as to efficientlyrelease the heat transmitted via a holding member 21 and transmit theheat to the door frame 45 provided in the heat exchange relation withrespect to the illumination attachment portion 46. Moreover, referencenumeral 47 in the drawing is an insulating material with which a spacesurrounded by the illumination attachment portion 46 and the rearsurface of the door frame 45 is filled.

According to such a constitution, the gasket 7C on the rear surface ofeach glass door 7 comes in close contact with the edge of thefront-surface opening 6 and the door frame 45 constituting the frontsurface of the pillar 8, to close the display chamber 5.

Moreover, shelf pillars 10 are vertically provided in the back surfaceand front part of the display chamber 5, and a plurality of stages ofshelves 9 are disposed on the shelf pillars 10. It is to be noted thatthe shelf pillars 10 are provided with a plurality of engagement holesformed with a predetermined space being left between the holes. When theengagement holes for disposing the shelves 9 are changed, the heightpositions of the shelves 9 can be changed.

It is to be noted that in the present embodiment, the shelf pillars 10are provided in the back surface and front part of the display chamber 5behind the pillars 8. Therefore, the plurality of stages of shelves 9are disposed behind the glass doors 7.

Furthermore, in the upper part of the display chamber 5, a cooler and ablower constituting a cooling apparatus R (shown only in FIG. 6) areinstalled. The cooler constitutes the cooling apparatus in which aso-called refrigerant cycle is constituted together with a compressor(not shown), a condenser (not shown) and the like separately installed.When cold air from this cooler is forcibly circulated through thedisplay chamber 5 by the blower, the inside of the display chamber 5 iscooled to a predetermined temperature.

Next, an LED illumination apparatus 15 provided in the display chamber 5will be described in detail with reference to FIGS. 2 to 5. FIG. 3 showsa side view of the LED illumination apparatus 15, FIG. 4 shows apartially enlarged view of FIG. 3, and FIG. 5 shows a partially enlargedview of a substrate 18, respectively.

In the present embodiment, the LED illumination apparatuses 15 arevertically provided on the inner side from the edge of the opening 6 ofthe insulating box body 2 constituting the main body, specifically onthe front corners of the display chamber 5 and the pillars 8. Each ofthe LED illumination apparatuses 15 is constituted of a plurality of LEDillumination members 16, holding members 21 holding the LED illuminationmembers 16 and attached on the inner side from the edge of the opening 6of the insulating box body 2, shades 30 and cover members 61.

As shown in FIG. 5, each of the LED illumination members 16 isconstituted of a substrate 18 provided with a plurality of LED elements17 and a plurality of electric heaters (resistors) 41, and the substrate18 is fixed to a satisfactorily thermally conductive attachment plate20. The substrate 18 is constituted so as to extend in a longitudinaldirection, and the substrate 18 is provided with the plurality of LEDelements 17 with a predetermined space being left between the elements.The LED elements 17 in the present embodiment are chip-type white LEDelements.

It is to be noted that the predetermined number of the LED elements 17regarded as one group are connected to a connector 42 provided in theend of the substrate, and the predetermined number of the electricheaters 41 regarded as one group are similarly connected to theconnector 42 in parallel with the LED elements 17. Moreover, theattachment plate 20 is provided with screw holes so that the plate isfixed to the holding member 21 with screws.

The holding member 21 is a satisfactorily thermally conductive metalmember constituted so as to vertically extend with respect to thefront-surface opening 6 of the insulating box body 2. The holding member21 has a substantially U-shaped section, and the upper and lower ends ofthe member are closed by the cover members 61. This holding member 21abuts on the illumination attachment portion 46 constituting the pillar8 or the rear surface of the front wall of the insulating box body 2constituting the front corner, when attached.

That is, a side wall 24 of the holding member 21 which faces thesubstantially U-shaped opening abuts on the illumination attachmentportion 46 of the pillar 8 formed so as to extend rearwards, and isfixed to the portion with screws (not shown). This side wall 24 isprovided with a plurality of vertically long extending elongated holes26 . . . The elongated holes 26 are holes to be superimposed on thescrew holes of the attachment plate 20 of the LED illumination member 16so that the holding member is fixed with the screws, and the verticalattachment position of the LED illumination member 16 can be changed asmuch as the length dimension of the elongated holes 26 (the attachmentposition can be changed in an arrow direction of FIG. 4).

Moreover, the rear wall of the substantially U-shaped holding member 21is provided with an engagement portion 27 to be engaged with the shade30, and the front wall of the holding member is provided with areflective plate portion 23 positioned behind the insulating material 40of the pillar 8 and bent rearwards as much as a predetermined angle.

The shade 30 is constituted of a light transmitting colorlesstransparent material for covering the holding member 21 from theoutside, and the shade is detachably attached to the holding member 21with decorative screws or the like.

A procedure for attaching the LED illumination apparatus 15 having sucha constitution will be described. First, the holding member 21 isattached on the inner side from the edge of the opening 6 of theinsulating box body 2. In the present embodiment, since the LEDillumination apparatuses 15 are positioned on both sides of each glassdoor 7, the holding members are attached to both front corners of thedisplay chamber 5 and the rearward extending illumination attachmentportions 46 of the pillars 8. It is to be noted that since the pillar 8is positioned between the glass doors 7 and 7, two holding members 21are attached via the illumination attachment portions 46 provided on thepillar 8 so that the back surfaces of the side walls 24 face each other.Moreover, the LED illumination apparatuses 15 provided in the frontcorners are attached so that irradiation light from the LED elements 17is emitted toward the inside of the display chamber 5.

Then, the attachment plates 20 provided with the LED elements 17 areattached to the side walls 24 of the holding members 21, and the screwholes of the attachment plates 20 are superimposed on the elongatedholes 26 to fix the attachment plates with the screws. In consequence,the substrate 18 of the LED illumination apparatus 15 is provided on thesurface of the door frame 45 on the display chamber 5 side in a heatexchange relation via the attachment plate 20 constituted of thesatisfactorily thermally conductive material and the side wall 24 of theholding member 21. Moreover, since the illumination attachment portion46 of the pillar 8 fixed to the side wall 24 is formed so as to tilt asmuch as the predetermined angle behind the center of the pillar 8 asdescribed above, the LED elements 17 of the LED illumination apparatus15 are provided on the display chamber 5 side slightly from a positionparallel to the front-surface opening 6.

It is to be noted that in the present embodiment, the plurality of(four) LED illumination members 16 described above are attached to theholding member 21. However, the LED illumination apparatus 15 may beconstituted of the single LED illumination member 16 constituted acrossthe upper and lower ends of the front-surface opening 6, and thevertical position of the apparatus may be changed in accordance with theelongated holes 26 for the attachment. When the apparatus is constitutedof a plurality of LED illumination members 16 as in the presentembodiment, production cost can be decreased, and handleability can beimproved.

Moreover, the reflective plate portion 23 of the holding member 21 ispositioned on the glass door 7 side of the LED illumination member 16.Furthermore, on the opening side of the holding member 21, the shade 30for covering the LED illumination member 16 from the outside isattached. It is to be noted that the shade 30 is detachably engaged withthe engagement portion 27 formed on the opening side of the holdingmember 21 and the end of the reflective plate portion 23. Inconsequence, the shade 30 is attached so that the shade is directed tothe inside of the display chamber 5 slightly from a positionsubstantially parallel to the glass door 7.

Next, a control apparatus C of the showcase 1 of the present embodimentwill be described with reference to FIG. 6. The control apparatus C ofthe present embodiment is constituted of a versatile microcomputer. Thiscontrol apparatus on an input side is connected to an illuminationswitch 53 of the LED illumination apparatus 15, a person detectingsensor 11 which detects that a person has approached the showcase 1, anillumination intensity sensor 48 for detecting an illumination intensity(the surrounding illumination intensity) in the store or the like wherethe showcase 1 is installed, a door opening/closing switch (dooropening/closing detection means) 49 for detecting the opening/closing ofeach glass door 7, and an in-chamber temperature sensor 50 for detectinga temperature in the display chamber 5.

The illumination intensity sensor 48 is provided on the outer surface ofthe main body 2, for example, the top surface of the main body as aposition which is not easily influenced by the shade of a peripheraldevice. As to the door opening/closing switch 49, since the plurality of(three) glass doors 7 are provided in the present embodiment, dooropening/closing switches 49A, 49B and 49C corresponding to the glassdoors 7 . . . are provided in order from the left glass door 7 as onefaces the front surface. It is to be noted that the person detectingsensor 11 will be described later.

Moreover, the control apparatus C on an output side is connected to thecooling apparatus R constituted of the compressor, the blower and thelike as described above, and is also connected to the LED elements 17and the electric heaters 41 of the LED illumination apparatus 15,respectively. It is to be noted that the LED elements 17 are connectedto the control apparatus C via an inverter 54. In addition, the controlapparatus C on the output side is connected to a temperature displaysection (temperature display means) 51 provided on the front surface ofthe upper part of the main body 2 so as to display the temperature inthe display chamber 5 or the present mode.

Here, as shown in an electric circuit diagram of FIG. 7, the persondetecting sensor 11 is connected to an LED illumination control section32 constituting the control apparatus C via a terminal plate 31 forconnection to the person detecting sensor. The person detecting sensor11 is provided on, for example, the front surface of the center of theupper part of the insulating box body 2 or the like, and has therein apower source 33 of the person detecting sensor itself, and a persondetecting contact 34 which detects the approaching of the person to openor close. The power source 33 is connected to a power source terminal35, and both sides of the person detecting contact 34 are connected toan output contact terminal 36 and a common contact terminal 37.

On the other hand, the terminal plate 31 provided in the showcase 1 mainbody is provided with a first connecting portion 55, a second connectingportion 56 and a third connecting portion 57. The first connectingportion 55 is connected to the power source on the side of the showcase1 main body and the LED illumination control section 32, the secondconnecting portion 56 is connected to the LED illumination controlsection 32, and the third connecting portion 57 is connected to thepower source on the side of the showcase 1 main body via theillumination switch 53 provided in the showcase 1 main body. Moreover,the power source on the side of the showcase 1 main body is connected tothe LED elements 17 of the LED illumination apparatus 15 via a DC powersource unit 58 in parallel with the LED illumination control section 32.

According to such a constitution, the power source terminal 35 of theperson detecting sensor 11 is connected to the first connecting portion55 of the terminal plate 31, the output contact terminal 36 of theperson detecting sensor 11 is connected to the second connecting portion56 of the terminal plate 31, and the common contact terminal 37 of theperson detecting sensor 11 is connected to the third connecting portion57 of the terminal plate 31. Consequently, in a state in which theillumination switch 53 on the main body 2 side is turned on, when theperson detecting contact 34 of the person detecting sensor 11 turnsON/OFF, the energization of the LED illumination control section 32 ofthe LED illumination apparatus 15 can be controlled. In consequence, theON/OFF control of the LED illumination apparatus 15 can be performedbased on the turning ON/OFF of the person detecting sensor 11. It is tobe noted that when the person detecting sensor 11 is turned on and thenturned off, the LED illumination control section 32 turns off the LEDillumination apparatus 15 after delay of a predetermined time of, forexample, several ten seconds from a time when the person detectingsensor 11 is turned off.

It is to be noted that in a state in which the terminals 35, 36 and 37of the person detecting sensor 11 are not connected to the terminalplate 31, that is, in a state in which the person detecting sensor 11 isdetached, as shown in FIG. 7, a short circuit line 60 is connectedbetween the second connecting portion 56 and the third connectingportion 57 of the terminal plate 31 to cause short-circuiting, wherebythe ON/OFF control of the LED illumination apparatus 15 can be performedby the ON/OFF control of the illumination switch 53 provided in the mainbody 2. Therefore, when the person detecting sensor 11 is connected, theON/OFF control of the LED illumination apparatus 15 can be performed bythe ON/OFF control of the person detecting contact 34 provided in theperson detecting sensor 11. Moreover, when the person detecting sensor11 is not connected, the short circuit line 60 causes the short circuitof each connecting portion of the terminal plate 31, so that the ON/OFFcontrol of the LED illumination apparatus 15 can be performed only bythe illumination switch 53 on the main body 2 side.

The illumination control of the LED illumination apparatus 15 of theshowcase 1 in the present embodiment having the above constitution willbe described. First, the control apparatus C detects an illuminationintensity in the store (the surrounding area) where the showcase 1 isinstalled by the illumination intensity sensor 48, and determines themaximum illumination intensity of the LED illumination apparatus 15provided in the display chamber 5 based on the illumination intensity.In the present embodiment, the maximum illumination intensity isdetermined so that the inside of the display chamber 5 is brightened asmuch as a predetermined illumination intensity as compared with thesurrounding illumination intensity detected by the illuminationintensity sensor 48.

Moreover, in a state in which the person detecting sensor 11 isconnected to the terminal plate 31 as described above, the controlapparatus C energizes the LED elements 17 of the LED illuminationapparatus 15 by the LED illumination control section 32 based on thedetection output of the person detecting sensor 11 indicating that theperson has approached the showcase 1, that is, the person has entered apredetermined range of a distance from the showcase 1. Therefore, inprinciple, the LED elements 17 of each LED illumination apparatus 15 arenot energized and are turned off in a state in which the persondetecting sensor 11 does not detect the approaching of the person.

At this time, based on the detection of the approaching of the person bythe person detecting sensor 11, the LED illumination control section 32of the control apparatus C controls a current/voltage for energizing theLED elements 17 of the LED illumination apparatus 15 so as to graduallyincrease the illumination intensity from a state in which the elementsare turned off. Finally, the illumination intensity is increased to themaximum illumination intensity determined based on the surroundingillumination intensity as described above.

In consequence, the illumination intensity of each LED element 17 forilluminating the inside of the display chamber 5 is gradually increasedbased on the detection of the approaching of the person by the persondetecting sensor 11 provided in the showcase 1. Therefore, as comparedwith a case where the display chamber is rapidly illuminated by the LEDelements 17 with a predetermined high illumination intensity, a customercan gradually be adapted to lights which can avoid a disadvantage thatthe customer is dazzled by the light or the like.

Here, the light from the LED elements 17 of the LED illumination members16 fixed to the side walls 24 of the holding members 21 is emitted in alateral direction (substantially parallel to the glass door 7) behindboth the side portions of the glass door 7. It is to be noted that inthe present embodiment, the LED elements are formed so as to slightlytilt rearwards (toward the display chamber 5 side) with respect to theedge of the opening 6 of the insulating box body 2 as described above.In consequence, the light from the LED illumination apparatus 15 isemitted toward the front parts of the shelves 9 disposed in the displaychamber 5. Therefore, the light having high directivity can be emittedfrom the LED elements 17 to the front parts of the shelves 9. Inconsequence, the commodities on the shelves 9, especially on theforemost parts of the shelves can evenly satisfactorily be illuminated,and the front surfaces of the commodities can effectively beilluminated. Consequently, the illumination effect and display effect ofthe commodities can be improved.

Moreover, in this case, the LED illumination control section 32 of thecontrol apparatus C gradually increases the illumination intensity fromthe state in which the LED elements 17 are turned off, and the sectionilluminates the inside of the display chamber 5 with the maximumillumination intensity determined based on the surrounding illuminationintensity. Therefore, the brightness of each LED element 17 of the LEDillumination apparatus 15 of the showcase 1 can be determined inaccordance with the brightness of a surrounding area such as the storewhere the showcase 1 is installed, and incompatibility with thesurrounding illumination can be avoided.

In consequence, the inside of the display chamber 5 can effectively beilluminated by the LED illumination apparatus 15 with an appropriateillumination intensity, and the improvement of the illumination effectcan be realized.

Furthermore, based on the non-detection of the approaching of the personby the person detecting sensor 11, after the elapse of a predeterminedtime of, for example, several ten seconds from a non-detection time, theLED illumination control section 32 of the control apparatus C stops theenergization of the LED elements 17 of the LED illumination apparatus 15to turn off the LED elements.

Thus, in the control apparatus C, when the person approaches theshowcase 1, the showcase is illuminated by the LED illuminationapparatus 15 with a bright illumination intensity, so that it ispossible to suppress the high rise of running cost due to the lightingof the LED illumination apparatus 15 more than necessary.

On the other hand, the LED illumination control section 32 of thecontrol apparatus C executes presenting illumination in a state in whichthe LED illumination apparatus 15 is lit while the person detectingsensor 11 detects the approaching of the person as described above, orfor a predetermined time after the non-detection of the approaching ofthe person.

In this presenting illumination, the control apparatus C controls thecurrent/voltage for energizing the LED elements 17 of the LEDillumination apparatus 15 to perform the bright/dark control of theillumination intensity of the LED illumination apparatus 15 periodicallybetween the maximum illumination intensity and the turned-off state. Itis to be noted that in the present embodiment, the LED elements areturned off as a dark state, but this is not restrictive, and the darkillumination intensity may have a predetermined minimum illuminationintensity (a state in which the LED elements are not turned off).

In consequence, the illumination presentation effect of the LEDillumination apparatus 15 can be improved, and the sales effect of thecommodities in the display chamber 5 can be improved.

On the other hand, in a case where one of the glass doors 7 is opened ina state in which the LED illumination apparatus 15 is lit as describedabove, based on the detection of the door opening by the dooropening/closing switch 49 (49A to 49C) which detects the opening/closingof the door 7, the control apparatus C controls the current/voltage forenergizing the LED elements 17 of the LED illumination apparatus 15illuminating the display chamber 5 part closed by the correspondingglass door 7 to decrease the illumination intensity of the LEDillumination apparatus 15. Moreover, based on the door opening/closingswitch 49 detecting that the corresponding glass door 7 has been closed,the control apparatus C lights the LED illumination apparatus 15 with anoriginal illumination intensity, that is, the maximum illuminationintensity in this case.

For example, in a case where the leftmost glass door 7 as one faces thefront surface is opened, the door opening/closing switch 49A detectsthat the glass door 7 has been opened. Based on this detection, thecontrol apparatus C decreases the illumination intensities of the LEDillumination apparatuses 15 provided for the glass door 7, specifically,the LED illumination apparatus 15 provided in the left front corner ofthe display chamber 5 as one faces the front surface, and the LEDillumination apparatus 15 provided on a side opposite to the above LEDillumination apparatus 15 via the glass door 7, that is, the LEDillumination apparatus 15 provided on the left side of the pillar 8positioned on the left side as one faces the front surface.

Consequently, in a case where the door opening/closing switch 49 detectsthat the glass door 7 has been opened, the control apparatus C decreasesthe illumination intensity of the LED illumination apparatus 15.Therefore, the intense light from the LED illumination apparatus 15 tothe front part of the display chamber 5, which has been blocked by theclosed glass door 7, can be prevented from directly entering customer'seyes or the like at a time when the glass door 7 is opened.

In consequence, even when the customer performs the opening operation ofthe glass door 7, it is possible to suppress a disadvantage that thefrontward light leaking from the LED illumination apparatus 15illuminating the inside of the display chamber 5 is emitted to thecustomer and that the customer feels dazzled.

In this case, the control apparatus C may gradually or immediatelyperform the illumination intensity change accompanying theopening/closing operation of the glass door 7. When the illuminationintensity is gradually changed, the incompatibility with the presentingillumination of the whole showcase 1 can be eased. On the other hand,when the illumination intensity is immediately changed, it is possibleto early eliminate a disadvantage that the light to the front part ofthe display chamber 5 which has been blocked by the glass door 7 entersthe customer's eyes at a time when the glass door 7 is opened.

Next, there will be described the illumination intensity control of theLED illumination apparatus 15 in a trial operation mode during the trialoperation or maintenance of the showcase 1, or in a non-cooling modewhich is not involve a cooling operation. In principle, the controlapparatus C executes the illumination intensity control of the LEDillumination apparatus 15 as described above. At this time, to protectthe LED elements 17 of the LED illumination apparatus 15 which generateheat when energized, the control apparatus C beforehand holds, as a hightemperature value, an in-chamber temperature supposed as a temperaturehaving a high possibility that the LED illumination apparatus 15 itselfmight remarkably incur deterioration, failure or the like. It is to benoted that the high temperature value can arbitrarily be set.

Moreover, in a case where based on the temperature detected by thein-chamber temperature sensor 50 installed in the display chamber 5, itis detected that the temperature has reached the high temperature value,the control apparatus C controls the current/voltage for energizing theLED elements 17 of the LED illumination apparatus 15 to decrease theillumination intensity.

In the present embodiment, the illumination intensity is decreased to anillumination intensity of about 50% of the maximum illuminationintensity. It is to be noted that the illumination intensity is notlimited to this example, and based on the detection of the hightemperature value, the LED illumination apparatus 15 may be turned off,or the illumination intensity of the LED illumination apparatus 15 maygradually be decreased.

In consequence, the heat generated from the energized LED elements 17themselves of the LED illumination apparatus 15 can be decreased.Therefore, it is possible to avoid a disadvantage that the LEDillumination apparatus 15 is lit with the bright illumination intensityin a state in which the inside of the display chamber 5 is not cooled toa predetermined cooling temperature in the trial operation mode or thenon-cooling mode to abnormally heat the LED elements 17 of the LEDillumination apparatus 15 and cause the deterioration or failure of theelements themselves.

Moreover, when the control is performed so as to decrease theillumination intensity of (or turn off) the LED illumination apparatus15 based on the detection of the high temperature value, the controlapparatus C displays the trial operation mode or the non-cooling mode atpresent by the temperature display section 51 provided in the main body2 of the showcase 1.

In consequence, at present, a user can be informed that the control isperformed so as to decrease the illumination intensity of the LEDillumination apparatus 15, and it can be recognized that the displaychamber is not darkened owing to the failure or the like.

Even when the illumination intensity of the LED illumination apparatus15 is controlled as described above, each LED element 17 constitutingthe LED illumination apparatus 15 has a high durability against turningON/OFF as compared with a fluorescent lamp heretofore used as theillumination apparatus, and the element can secure a predeterminedillumination intensity following ON/OFF control even under anenvironment at a low temperature, so that appropriate illuminationcontrol can be realized.

Moreover, the LED element 17 has a remarkably long life as compared withthe fluorescent lamp, and hence can obviate the need for an illuminationreplacing operation. In consequence, the need for a laborious operationsuch as the constant storage of a replacing component or the disposal ofwastes discharged due to the replacement can be obviated.

On the other hand, when the LED elements 17 are energized by the controlof the current/voltage for energizing the LED elements 17 of each LEDillumination apparatus 15 as described above, the substrate 18 providedwith the LED elements 17 generates heat. As the energization is large,the heat increases. Therefore, when the inside of the display chamber 5is illuminated by the LED elements 17, the heat is transmitted to thesatisfactorily thermally conductive attachment plate 20 to which thesubstrate 18 is attached and the side wall 24 of the satisfactorilythermally conductive holding member 21 to which the attachment plate 20is attached.

Moreover, since this side wall 24 is provided so as to abut on the doorframe 45 made of the metal, the heat generated by the LED illuminationapparatus 15 is transmitted to the door frame 45 provided in a heatexchange relation. Since the door frame 45 comes in contact with theoutside, dew condensation is easily caused by a difference between theoutside air temperature and the temperature in the display chamber 5.However, the door frame 45 can be heated by the heat generated by theLED illumination apparatus 15, and hence the dew condensation of thedoor frame 45 can effectively be suppressed.

In consequence, it is possible to effectively avoid a disadvantage thatthe dew condensation occurs in the door frame 45 to wet the inside ofthe display chamber 5, the installation floor surface of the showcase 1or the like. Moreover, it is possible to avoid a disadvantage that thedew flies and scatters by the opening/closing operation of the glassdoor 7.

Moreover, when the heat generated by the energization of the LEDelements 17 is used in heating the door frame 45, the heat can smoothlybe released from the substrate 18 provided with the LED elements 17, andthe deterioration or failure of the LED illumination apparatus 15 can beprevented or suppressed. Furthermore, the deterioration of a coolingefficiency in the display chamber 5 can thus be decreased.

It is to be noted that in the above-mentioned illumination (illuminationintensity) control, when the inside of the display chamber 5 is notilluminated by the LED illumination apparatus 15, the heat generated bythe energization of the LED elements 17 cannot be used in heating thedoor frame 45.

Therefore, in the present embodiment, when the LED elements 17 of theLED illumination apparatus 15 are not energized, the control apparatus Cenergizes the electric heaters 41 provided on the substrate 18 togetherwith the LED elements 17.

In consequence, even when the LED illumination apparatus 15 is turnedoff and the door frame 45 cannot be heated by the heat generated by theapparatus itself, the heat of the electric heaters 41 generated by theenergization can be transmitted to the surface of the door frame 45 onthe display chamber 5 side to effectively suppress the dew condensationof the door frame 45.

Therefore, even when the LED illumination apparatus 15 illuminates theinside of the display chamber or is turned off, the LED elements 17 orthe electric heaters 41 constituting the LED illumination apparatus 15are energized. Consequently, unlike the conventional example, anelectric heater does not have to be especially embedded in the doorframe 45. In particular, since the surface of the door frame 45 on theglass door 7 side is heated by the energization of the LED elements 17,the need for the separate energization of the electric heater isobviated during the illumination by the LED illumination apparatus 15,and the running cost can be decreased.

It is to be noted that in the above present embodiment, the electricheaters 41 for heating the door frame 45 are provided on the substrate18 constituting the LED illumination apparatus 15 to heat the surface ofthe door frame 45 on the display chamber 5 side provided in a heatexchange relation with respect to the substrate 18, but this is notrestrictive, and a constitution shown in FIG. 8 may be used. That is,electric heaters 41 are not provided on a substrate 18 constituting anLED illumination apparatus 15, LED elements 17 only may be arranged onthe substrate, and electric heaters 52 may be embedded in the backsurface of a door frame 45 constituting a pillar 8. The electric heaters52 heat the surface of the door frame 45 on a glass door 7 side byenergization, and a control apparatus C energizes the electric heatersaccompanying the stop of the energization of the LED elements 17 of theLED illumination apparatus 15.

In consequence, when the LED illumination apparatus 15 is turned off,the electric heaters 52 for heating the surface of the door frame 45 onthe glass door 7 side can be energized to effectively suppress the dewcondensation of the door frame 45.

1. A showcase in which the inside of a display chamber constituted in amain body so as to display commodities is illuminated by an LEDillumination apparatus, comprising: a glass door which openably closesan opening of the display chamber; and a metal door frame which isprovided in the main body so as to constitute an opening edge of thedisplay chamber and on which the glass door abuts, wherein the LEDillumination apparatus is provided on the surface of the door frame onthe side of the display chamber in a heat exchange relation.
 2. Theshowcase according to claim 1, further comprising: an electric heaterwhich heats the surface of the door frame on the side of the glass door,wherein the electric heater is energized at a time when the LEDillumination apparatus is turned off.
 3. The showcase according to claim1, wherein the LED illumination apparatus includes an electric heater,and the electric heater is energized at a time when the LED illuminationapparatus is turned off.